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21.
Objective: Normosmic idiopathic hypogonadotropic hypogonadism (nIHH) is characterized by failure of initiation or maintenance of puberty due to insufficient gonadotropin release, which is not associated with anosmia/hyposmia. The objective of this study was to determine the distribution of causative mutations in a hereditary form of nIHH. Methods: In this prospective collaborative study, 22 families with more than one affected individual (i.e. multiplex families) with nIHH were recruited and screened for genes known or suspected to be strong candidates for nIHH. Results: Mutations were identified in five genes (GNRHR, TACR3, TAC3, KISS1R, and KISS1) in 77% of families with autosomal recessively inherited nIHH. GNRHR and TACR3 mutations were the most common two causative mutations occurring with about equal frequency. Conclusions: Mutations in these five genes account for about three quarters of the causative mutations in nIHH families with more than one affected individual. This frequency is significantly greater than the previously reported rates in all inclusive (familial plus sporadic) cohorts. GNRHR and TACR3 should be the first two genes to be screened for diagnostic purposes. Identification of causative mutations in the remaining families will shed light on the regulation of puberty.  相似文献   
22.

Purpose

Aneurysmal bone cyst is a benign, relatively uncommon lesion, representing 1.4 % of primary bone tumors. The vertebral column is involved in 3–30 % of cases. This report describes clinical characteristics and treatment results of 18 patients with aneurysmal bone cyst of the spine.

Methods

Between 1991 and 2008, 18 patients with aneurysmal bone cyst of the spine were surgically treated in our department. The clinical records, radiographs, histologic sections, and operative reports were analyzed.

Results

There were 11 male and 7 female patients; mean age was 22.1 years (range 7–46 years). Localizations were cervical (3), cervicothoracic (2), thoracic (3), lumbar (4), and sacrum (6). Tumor was localized on the left side in 11 cases, on the right side in 2 and at midline in 5 patients. The two most common clinical features were axial pain (14 patients) and radicular pain (8 patients). Neurological signs were paraparesis in 3, monoparesis in 6. Mean duration of symptoms was 9 months (range 3 months–3 years). All patients underwent surgery: total removal was performed in 13 patients and subtotal resection in 5. Posterior (11), anterolateral (1), or combined anterior-posterior (6) approaches were used. Mean follow-up duration was 112.3 months (range 4–21 years). We detected four recurrences in subtotal excision group (4/5), and one recurrence in total excision group (1/13).

Conclusion

Treatment options for aneurysmal bone cysts are simple curettage with or without bone grafting, complete excision, embolization, radiation therapy, or a combination of these modalities. Radical surgical excision should be the goal of surgery to decrease the recurrence rate. Recurrence rate is significantly lower in case of total excision.  相似文献   
23.
We performed this dosimetric study to compare a nonstandard volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) techniques with high-dose rate (HDR) brachytherapy (BRT) plan of vaginal vault in patients with postoperative endometrial cancer (EC). Twelve postoperative patients with early stage EC were included in this study. Three plans were performed for each patient; dosimetric and radiobiological comparisons were made using dose-volume histograms and equivalent dose for determining the planning target volume (PTV) coverages in brachytherapy and external beam radiotherapy, and organs-at-risk (OARs) doses between three different delivery techniques. All the plans achieved adequate dose coverage for PTV; however, the VMAT plan yielded better dose conformity, and the HT plan showed better homogeneity for target volume. With respect to the OARs, the bladder D2cc was significantly lower in the BRT plan than in the VMAT and HT plans, with the highest bladder D2cc value being observed in the HT plan. However, no difference was observed in the rectum D2cc of the three plans. Other major advantages of the BRT plan over the VMAT and HT plans were the relatively lower body integral doses and femoral head doses as well as the fact that the integral doses were significantly lower in the BRT plan than in the VMAT and HT plans. This is the first dosimetric comparison of vaginal vault treatment for EC with BRT, VMAT, and HT plans. Our analyses showed the feasibility of stereotactic body radiotherapy technique as an alternative to HDR-BRT for postoperative management of EC patients.  相似文献   
24.
Biomimetic three-layered monolithic scaffold (TLS) intended for the treatment of osteocondral defects was prepared by using alginate, chitosan and β-tricalcium phosphate (β-TCP) to study drug release behavior of the alternative drug delivery system and to investigate the therapeutic efficacy of the scaffold. Dexamethasone sodium phosphate (Dex) as a model drug was incorporated into the scaffold by solvent sorption method and in vitro release studies were conducted. In addition, the scaffold was implanted into the defects formed in the trochlea of Sprague–Dawley rats to assess the healing potential of the TLS on the osteochondral defect against reference Maioregen® comparatively. The release studies showed that after an initial burst at 3rd h, dexamethasone is released slowly during a 72-h period. In vivo studies indicated that the TLS has good tissue biocompatibility and biodegradation rate and showed better results during osteochondral healing process compared to the reference. All results demonstrated that the alginate-chitosan/β-TCP scaffold could be evaluated as a good candidate for osteochondral tissue applications.  相似文献   
25.
BACKGROUND: Umbilical defects may cause technical problems for general surgeons in patients during laparoscopic cholecystectomy (LC) operations and may increase the incidence of incisional hernia. AIM: The objectives of this study were to determine the optimal repair method for umbilical hernias that already exist or are encountered incidentally and to present data regarding potential problems that may occur during LC. SETTINGS AND DESIGN: Medical records of patients who had received simultaneous umbilical hernia repair (UHR) with LC were investigated retrospectively. MATERIALS AND METHODS: Cholelithiasis was accompanied by umbilical hernia in 64 (8.6%) out of 745 patients who underwent LC and UHR simultaneously in our hospital between 2000 and 2004. STATISTICAL ANALYSIS USED: The Mann-Whitney U, Chi-square, One-Way Anova, Kaplan-Meier survival analysis, the log-rank test and t test were used for statistical analyses. RESULTS: LC was followed by UHR using primary suture (Group 1), Mayo repair (Group 2) and flat mesh-based repair (Group 3) in 32 (50%), 18 (28.1%) and 14 (21.9%) patients, respectively. Mean body mass indexes (BMI) of patients were 26.6 kg/m 2, 29.2 kg/m 2 and 39.9 kg/m 2 in Groups 1, 2 and 3, respectively. Recurrence rates were 9.4%, 5.6% and none (0%) in Groups 1, 2 and 3, respectively. Recurrence was observed in three (7.0%) out of 43(67.2%) patients with BMI > or = 30 kg/m 2 while umbilical hernia recurred in one (4.8%) out of 21 (32.8%) patients with BMI < 30 kg/m 2. Overall morbidity and mortality rates were 14.1% and 0%, respectively. CONCLUSIONS: The outcomes of the UHR with mesh after laparoscopic surgeries appear to be better for either obese or non-obese patients than primary suture techniques in recurrence rates.  相似文献   
26.
27.
PURPOSE: The purpose of this study was to evaluate the efficacy of three desensitizing agents vs. placebo. MATERIALS AND METHODS: One hundred and six hypersensitive teeth of 26 patients were included in this study, and the baseline hypersensitivity level of all teeth was established as 'moderate' by using Visual Analogue Scale (VAS). The teeth were divided into four groups: to the first group 5% potassium nitrate bio-adhesive gel, to the second 2% sodium fluoride bio-adhesive gel and to the third one step adhesive system Prompt L-Pop were applied as desensitizing agents. Group 4 was the control group in which a desensitizer-free bio-adhesive gel was used as placebo. Post treatment and eighth week control measurements were recorded on VAS. RESULTS: It was observed that the efficacy of three desensitizing agents did not differ from each other (P >0.05) and except for placebo all reduced moderate dentin hypersensitivity effectively (P <0.05). Clinical relevance: Five per cent potassium nitrate, 2% sodium fluoride bio-adhesive gels and one-step bonding agent Prompt L-Pop were effective in reducing moderate dentine hypersensitivity.  相似文献   
28.
29.
OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients.  相似文献   
30.
Background: Aortic stiffness is an independent risk factor for cardiovascular events and mortality. The measurement of pulse‐wave velocity (PWV) is the most simple, noninvasive, and robust method to determine aortic stiffness. Whether aortic stiffness contributes to aortic valve sclerosis (AVS) remains unknown. The aim of the present study was to examine the relationship between PWV and AVS in subjects free of clinically evident atherosclerotic disease. Methods: We enrolled 62 patients (48 men; age 65 ± 8 years) diagnosed with AVS and an additional 62 age‐, hypertension‐, diabetes mellitus‐, and history of smoking‐matched subjects without AVS. Applanation tonometry was applied to assess the augmentation index and aortic PWV. The subjects with symptomatic vascular disease were excluded from the study. AVS was defined by echocardiography as thickening and calcification of the normal trileaflet aortic valve without obstruction to the left ventricular outflow. Results: There was no significant difference between the two groups regarding the aortic PWV and augmentation index (11.7±3.3 vs 11.8±3.7, P=0.85; 28.0±9.4 vs 25.0±8.6, P=0. 17, respectively). The presence of AVS was significantly correlated with ejection fraction (r=0.211, P=0.011), male gender (r=0.362, P=0.0001), and age (r=0.200, P=0.026). Conclusions: The lack of an association between the aortic PWV and AVS suggests that AVS is a complex phenomenon consisting of several distinct processes, related to both atherosclerotic and nonatherosclerotic processes.  相似文献   
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